CVE-2026-81887Network attack vectorHinoki check available

DOM XSS via inherited client-side effects

Published Aug 31, 2026 · Updated Sep 3, 2026

DOM-based XSS in Livewire 3.0.0-beta.1 through 3.8.2 and 4.0.0-beta.1 through 4.3.3 allows remote attackers to execute JavaScript via crafted URLs. The dot-notated query-string parser accepts prototype-related path segments, creating inherited properties that effect handlers trust without own-property checks. Exploitation requires a user to open the crafted URL and runs code only with the affected user's application-origin privileges.

CVSS severity5.1
Medium
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

DOM-based XSS in Livewire 3.0.0-beta.1 through 3.8.2 and 4.0.0-beta.1 through 4.3.3 allows remote attackers to execute JavaScript via crafted URLs. The dot-notated query-string parser accepts prototype-related path segments, creating inherited properties that effect handlers trust without own-property checks. Exploitation requires a user to open the crafted URL and runs code only with the affected user's application-origin privileges.

The record

CVE
CVE-2026-81887
Published
Aug 31, 2026
Updated
Sep 3, 2026
Vendor
Livewire
Product
Livewire
Classifications
CWE-79, CWE-1321, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 3.0.0-beta.1, < 3.8.3
  2. Affected versionversion=>= 4.0.0-beta.1, < 4.3.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Livewire · Livewireversion=>= 3.0.0-beta.1, < 3.8.3; version=>= 4.0.0-beta.1, < 4.3.4

Published CVSS scores

5.1GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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